Process for breaking petroleum emulsions



"Patented Apr. 10, 1945 l mocnss FOB namxme PETROLEUM muns rons I MelvinDe Groote, University City, and Bernhard Keiser,

Webster Groves,

Mo., assignors to Petrolite Corporation, Ltd., Wilmington, Did, a

corporation of Delaware No Drawing. Application March 9, 1943,

Serial No. 478,596

6 Claims. (Cl. 252-341) This invention relates primarily to theresolution of petroleum emulsions.

One object of our invention is to provide a novel process for resolvingpetroleum emulsions of the wa'ter-in-oil type, that are commonlyreferred to as cut oil, roily oil, emulsified oil, etc., and whichcomprise fine droplets of naturally-occurring waters or brines dispersedin-a more or less permanent state throughout the oil which constitutesthe continuous phase of the emulsion.

Another object of our invention is to provide an economical and rapidprocess for separating emulsions which have beenprepared undercontrolled conditions from mineral oil, such as crude petroleum, andrelatively soft waters or weak brines. Controlled emulsification andsubsequent demulsification under conditions just mentioned, is ofsignificant value in removing impurities, par,- ticularly inorganicsalts, from pipelineoil.

- The deinulsifier r demulsifying agent employed in our process consistsof the resultant products obtained by reaction involving polybasiccarboxy acids, preferably and conveniently in the form of an ester, suchas diethyl phthalate, and acylated ureas, and particularly acylatedsubstituted ureas having in the most preferred. form, at least one, andmore Such acylatedureas, or' substituted ureas, are of the kind in whichthe acyl radical which is introduced is derived from detergent-formingmonocarboxy acids containing eight carbonatoms or more, and not morethan 32 carbon atoms, and.

are characterized by the fact that they combine .with alkalis-toproducesoap or soap-like mate- -rials.- -These detergent-forming -acids includefatty acids, resin acids, petroleumacids, etc. For the sake ofconvenience, these acids will be indicated by the iormtila'RflOOH.Certain derivatives of detergent-forming acids react with alkali toproduce soap or. soa'p like materials, and ,4 are the obviousequivalent-of the unchanged or unmodified detergent forming acids; for.in-. stancerinstead of fatty acids,one might employ preferably, at leasttwo hydroxyl radi- Acids alsotrue in regard to primary amines, such as9, 1943. Said co-pending applications describe new compositions ofmatter, for instance, the acylated derivatives of reaction productsobtained by combination with diethanolamine and diethyl carbonate. Thisis illustrated in a very simple .aspect by the three followingreactions:

ethyl ethanolamine, ethyl propanolamine, ethyl butanola'mine, propylethanolamine, propyl propanolamine, cyclohexyl ethanolamine, benzylethanolamine, phenyl ethanolamine, etc. This is monoethanolamine,monopropanolamine, monobutanolamine, monopentanolamine,monohexanolamine, etc.

Reconsidering the three reactions immediately preheding, it is obviousthat they may be considagent having a reactive ethylene oxide ring, and

forni'ing acyl group into a molecule or compound of the kind previouslydescribed by the use of Reference is made to our co-pending applica- 7'tions Serial Nos. 478,595 and 478,594, filed March ered as substitutedureas, substituted urethanes, and carbonic acid esters; The-'uiethanesare, of course, esters'of carbamic acid. It is also obvious that theproducts of reaction above described, the

esters, urethanes, the substituted ureas, etc., can

be treated with ethylene oxideor some other resubsequentlyacylated'witba high molal monocarboxy acid.

-One may introduce ahigh molal detergentsuitable' reactants, such asethyl oleate, ethyl naphthenate, ethyl resinate, etc., all of whichisdescribed in detail in said aforementioned copending applications.

Attention is, directed to U. S. pate'ntto' De Cirootev No. 2,083,22Ldated June 8, 1937, and'No.

2,059.27 3, dated November 3, 1936, to Piggott. It is :to be noted thatsaid, aforementioned De Groote patent gives a more ,elaboratedescription of. the monocarboxy detergent-forming acids-hereincontemplated as reactants. It is also believed, in the light ofsubsequent investigations, that in many instances reaction with acompound having a reactive ethylene oxide ring, such as ethylene oxide,propylene oxide, butylene oxide, glycid, or the like, may result in thecomplete elimination of an amino hydrogen atom; as shown in both of saidaforementioned patents, i. e., the De Groote and Piggott patents.

It is also obvious that substituted ureas in considerable variety andsuitable. for use as a reactant in preparing compounds of the kindherein contemplated, both for use as demulsifiers and for other uses,are readily obtainable from a variety of amines.

It may be well to point out that our preferred fatty acids, forinstance, oleic, ricinoleic, linoleic, linolenic, stearic, lauric, etc.One need not employ a single higher fatty acid, but may employ the fattyacids, particularly in ester form, as derived from various naturalsources. In other words, one may employ the fatty acids or esters offatty acids as they occur in mixed form in cottonseed oil, corn oil,castor oil, soyabean oil, olive oil, cocoanut oil, teaseed oil, linseedoil, etc.

In many instances, one need not separate the acylated ureas, orsubstituted press, of the kind herein described from other members of acogeneric mixture, such as esters of carbonic acids,

or 'urethanes. Previous reference in regard to this aspect has alreadybeen made in connection with our two co-pending applications Serial Nos.

The

478,594 and 478,595, flied March 9, 1943. use of such cogeneric mixturesas reactants will serve to yield a final product which containsasignificant amount of the compositions ornew compounds hereincontemplated.

Attention is further directed to the fact that in various examples,particularly those hereinafter described in detail, there is anintermediate step of oxyethylation prior to treatment with ethyl oleateor the like and diethyl phthalate or the like. It is to be noted that insome instances it is more advantageous to reverse the procedure andreact with a compound such as diethyl phthalate first, and then followwith an acylation reaction or the kind in which there is introduced ahigh molal detergent-forming monocarboxy radical or acylated radical. I

It is also of interest to note that,v as previo pointed out, theacylation reactions herein con- .15 detergent-forming acid, as-asource'of the re- 'quired vacyl radical, is exemplified by: the higherpiamylurea is prepared from amylamihe, and a cyanate. (See Berichte 12,1331, Custer.) Other equally suitable methods may be employed.

Sussrrmzp Um Example 2 The same procedure is followed'as in the pieceding example, except that cyclohexylamine is substituted foramylamine.

, Susanna-ran Um Example 3 'Ifhe same procedure-is followed as inExample 1, preceding, except that benzylamine is substituted foramylamine.

svssnrprrn URIA Efiomple '4 The same procedure is followed as in Example\1 preceding, except that aniline is substituted for amylamine. V

AMIDO-TYPI Ac'rmrsn sunsnrurxn Urns Example 1 Symmetrical diamyl urea isreacted with a low molal ester of a hydroxylated high molaldetergent-forming acid, such as the ethyl ester of ricinoleic acid, theethyl ester of hydroxystearic acid, the ethyl ester ,of dihydroxystearicacid, the ethyl ester ofhydroxylated acids obtained by the oxidation ofpetroleum .wax, etc. Equal molal ratios are employed. One amino hydrogenatom remains without entering into reaction.

Amino-TY" AcYum 8088mm Urns Example 2 The same procedureais followed asin the preceding example, except that instead oi employing the amylatedurea, one employs instead,

tempiated, whether involving the introduction of 7 an acyl radical froma high molal detergent forming monocarboxy acid, or the acyl radical ofa polybasic carboxy acid, need not be limited to the esteriflcaflon typeof acylation, i. e., reaction involving an alcoholic hydroxyl radical,but includes reactions involving an amino hydrogen atom, i. e.,amidiiication.

In other words, in some of the subsequently described examples, it

various substituted ur'eas described under the heading SubstitutedExamples 2-4."

- Oxntx'nxrstfbdssrrrum Urns 1 pound mole of four pound moles ofethylene oxide (see afore- -mentioned U. S. patent to De Groote No.2,083,221,

isiobvious that if oxyethylation were, omitted, the

product would still be susceptible to"reactio ns of the kind described,i.-- e;, acylstion reactions. n It would appear that perhaps thesimplest and most attractive reaction for the formation of compounds ofthe kind herein-contemplated, or

' rather, for. the formation of certain desirable intermediates, wouldbe a reaction involving the amide of a high molal detergent-formingacid,

such as oleoamide, ricinoleoamide, etc., with diethyl carbonate, or thelike, in the-ratio of-ctwo and U. S. patent to Pisgott No. 2,059,273)Oxmnmsrsn Sworn-mo Um Example 2 One pound mole of amylaied urea of thekind 'described'under the "Substituted ureas.

Example 1;".preced'in'g, is treated with two pound moles of ethyleneoxide so as to yield the corresponding oxyetbtrlated derivative.

.moles ofthe amidefor 121018 91 diethyl-carbonate, particularly intheprcsence of a small amount or catalyst, such as sodium'bicarbonate.

. Oxxmrnm Suns-11mm Um Example 3 IInsteadofemployingamylatedumaasareactant, one instead various othersubstitutediureas of the kind described under the previous headings2Bubstituted ureas, Examples 2-4, inclusive.

-urea. is' treated with at least Oxutmsrzo Um Example 4 The sameprocedure is followed as in the three preceding examples, except thatsome other reactant containing a reactive ethylene oxide ring, forinstance, propylene oxide, butylene oxide, glycid, or the like, areemployed instead of ethylene oxide.

ESTER-TYPE AcYLATan Su'esTITuTso UasAs Q Esample 1 Hydroxylatedsubstituted ureas, preferably having at least two alcoholic functions,arereacted with low molal esters of high molal detergent-forming acidswhich may or may not be.

hydroxylated, for example, one pound mole of an oxyalkylated ureaexemplified by Oxyalkylated Example 1, preceding, is reacted with onepound mole of ethyloleate.

EsTna-Trrn AcYLATeo SUesTITu'rEn UBEAS Example 2 Instead of using anoxyalkylated urea. of the kind exemplified by Example 2, preceding, oneemploys the type exemplified by Exampdes 3 or 4, preceding.

ESTER-TYPE AcYLAm SUBSTITUTED UREAS Example 3 Ethylricinoleate, or someother low molal ester, such as the methyl or propyl ester, issubstituted for ethyloleate in the preceding example.

ESTER-TYPE AcYLATsn SussTITuTeo UasAs Example 4 Ethyl naphthenate issubstituted for ethyloleate in Examples 1 or. 2, preceding.

ESTER-TYPE ACYLATED SussTITuTao UREAS Example 5 Ethyl resinate, preparedby the esterification of rosin with ethyl alcohol, is substituted forethyloleate in Examples 1 and 2, preceding.

FINAL Como'sITroN or MATm Example 1 1 pound mole of an amido acylatedsubstituted urea, as exemplified by the type of material described underExample 1, preceding, is'reacted with 1 pound mole of diethyl phthalate.The substituted urea is preferably reacted with 2 to 4 moles of anoiwalkylating agent, prior to re-.

action, with diethyl phthalate. is especially suitable.

FINAL ComrosrrroN or MATTER Example 2 The same procedure is followed asin Ester type acylated substituted ureas, Example 1, preceding, butthere is employed as a reactant the type of material described under theheading Ethylene oxide -Amido-type acylated substituted ureas, Ex-

ample 2i 4 FINAL COIIPOSITION or MATTER Example 3 The same procedure isfollowed as in Examples 1 and 2, preceding, but instead of the previousreactants employed in conjunction with diethyl phthalate, there isemployed instead a material of the kind described under the heading"Estertype acylated mibstituted ureas, Example 1.

FINAL ComosITIoN or Example 4 The same procedure is-followed as the pre-I ceding example, except that the reactant em ployed in conjunction withdiethyl phthalate is a material of the kind typified by "Ester-type Iacylated substituted ureas, Examples 2 to 5, in-

elusive."

FINAL COMPOSITION or MATTER Example 5 The same procedure is followed asin the preceding examples, except that where the reactant employed inconjunction with diethyl phthalate is polyfunctional, the molarproportion of di ethyl phthalate to the acylated intermediate (acyPhaving reference to thehigh molal detergent-forming monocarboxy acid.radical) is increased to a polymolecular proportion, for instance, 2 to1 or 3 to 1.

FINAL COMlOSI'HON or MATTER Earample 6 I The same procedure is followedas in the preceding Examples 1 to 5, inclusive, except that the diethylester of some other suitable polybasic carboxy acid, such as diethylmaleate, diethylfumarate, diethyl, adipeate', diethyl succinate, diethyl azaleate, diethyl citrate, diethyl citraconate, diethyl sebacate,diethyl tartrate, or the like, is employed;

' FINAL Como'sITIoN or M TTER Example 7 The same procedure is followedas in Examples 1 to 6, preceding, except that some other low molal alkylester, particularly a dialkyl ester, is employed instead of the diethylester. For instance, one might employ dimethylphthalate,

- 40 ethyl methyl phthalate, dipropyl phthalate,

methyl propyl phthalate, ethyl propyl phthalate, dibutyl phthalate,propyl butyl phthalate, ethyl butyl phthalate, etc. In various of theabove instances, the acid itself or anhydride, such as phthalicanhydride, maleic anhydride, citraconic anhydride, or the acid, such asadipic acid, azaleic acid, or the like, may be used.

Reference is again made to the fact that'it has been previously notedthat in some instances it is more-convenient and desirable to react aselected raw material or intermediate with a reactant such as diethylphthalate, or the like, and

subsequently react with ethyl oleate, ethyl ricin-- oleate, or the like.

In the preceding examples, it is to be noted that the reactions, inpart, involve conventional acylation, which generally-means theelimination of water, or an alcohol, or possibly, ammonia. In view ofthe employment of a reactant such as ethyl oleate, or ethyl ricinoleate,it is obvious that acylation will ,take'place with the eliminae tion ofethyl alcohol. Naturally, methyl oleate,

, methyl ricinoleate, propyl oleate, propyl ricinolestance, 2-12 hours.Completeness of reaction is generally indicated by the fact thatsubstantially the theoretical amount of alcohol, after making allowancefor impurities and mechanical loss, is evolved and may be condensed andmeasured. The same applies when the acylation reaction involves areactant such as diethyl phthalate, or the like. This is also true inregard to reactions involving diethyl carbonate. The diethyl carbonatereactions are sometimes catalyzed by the addition of a small amount, forinstance, approximately /i% to of sodium bicarbonate. 7

Conventional acylation reactions of the kind involved in the formationof oleoamide, or ricinoleoamide, are so well known that description isnot required.

We have found that the most suitable products for various purposes, andparticularly, for

demulsiflcation, are sub-resinous, semi-resinous, or balsamlikeproducts, and are preferably derived from' polyfunctional acylatedreactants, in which the acyl group is derived from a high molaldetergent-forming monocarboxy acid. We have found that suohproducts aresoluble to a in which q indicates a small whole number (one in the caseof a monomer, and probably not over 10, and usually less than 5, and mand n indicate the number 1 oimore, and m" and n" indicate zeroor asmall or moderately sized whole number, such as zero, one or more, butin any event, probably a number not in excess of 4-8.

fairly definite state, for' example, 5% in some solvent, such as water,alcohol, benzene, dichlo-- roethyl ether, acetone, .cresylic, acid,dilute acidic acid, dioxane, or the like. This is simply another way ofstating that it is preferable, that the product be one of thesub-resins, which are commonly referred to as an A resin, or a B resin,

'as distinguished from a C resin, which is a highly infusible, insolubleresin. (See Ellis, Chemistry of Synthetic Resins,'1935, page 862, etseq.)

It is our preference that the roducts'be obtained from polyhydroxylated'acylated products by reaction with diethyl phthalate, or the like.Indeed, it is our preference to employ polyhydroxylated acylatedproducts. of the kind in which there is no amino hydrogen atom present,i. e., the kindv in which acylation is limited entirelyto theesterification type of reaction.

In view of what has been said as to the runner 0115 and varied aspectsof the present invention, it is apparent that a monohydroxylatedacylated product free from an amino hydrogen atom, can form only amonomer such as a complete ester or fractional ester. Thus, if thehydroxylated acylment with a reagent containing a reactive Actually, inview of what has been said as to the most desirable procedure ofmanufacture, in order to avoid decomposition, it is obvious that thefree carboxyl atom above will not appear, but the ester radical, i. e.,one where the carboxylic hydrogen atom has been replaced by a methyl,ethyl, propyl, or butyl group, will appear.

It is also obvious that the solubility oi the reagents herein describedmaybe enhanced by oxyalkylation, i. e., the final composition ofmatter-exemplified by Examples 1 to 7, preceding, may, in variousinstances, be subjected/to treatethylene oxide ring, for example,ethylene oxide, propylene oxide, butylene oxide, glycid, etc. In suchinstances, the ethylene oxide'or equivalent reactant reacts with anyaminohydrogenatom present or any hydroxyl radical present, or may causea rearrangement or re-esterification -by.replacing a low mole alkylradical, such as an ethyl radical, by a hydroxy' ethyl radical, or anequivalent radical, in which the carbon atom chain is interrupted one ormore times by an oxygen atom. Compare reactions involved when aglyceride such as a castor oil or olive oilais treated with ethyleneoxide.

Conventional demulsifying. agents employed in the treatment of oil fieldemulsions are used as such, or after dilution with any suitable solvent,

. such as water; petroleum hydrocarbons, such as gasoline, kerosene,stove oil; a coal tar product,

ated products employed as reactants for combiwhere n indicates thenumber 2 or more, then the reaction between a monohydric alcohol and apolybasic acid will result in a compound which may be indicated by thefollowing formula: YX(COOH)1u, wherein n indicates the number 1 or more,and which is in'reality a contraction of a more elaborate structuralformula, in which X and Y are joined by a carboxyl radical or resi? due.Assuming, however, as would be true in the majority of cases, that thealcohol actually would be a poiyhydric alcohol, and 'that the'acid bodywould be polybasic in nature, for instance, if one employed adiphthalate of a polyhydroxylated ester diamide of thekind previouslydescribed, then examination reveals that the formula might result inacombination, in which therewere neither residual carboxyl radicals, norresidual such as benzene, toluene, xylene, tar acid oil,

cresol anthracene oil, etc. Alcohols, particularly aliphatic. alcohols,such as methyl alcohol, ethyl alcohol, denatured alcohol, propylalcohol, butyl' alcohol, hexyl alcohol, octyl alcohol, etcL, may beemployed as diluents. Miscellaneous solvents, such as pine oil, carbontetrachloride, sulfur dioxide extract obtained in the refining ofpetroleum, etc., may-be employed as diluents. Similarly, the material.or materials employed as the.

demulsifying agent of our process may be admixed with one or more of thesolvents customarily used in connection with conventional 5 apparentinsolubility in oil and water is not sigic acid, and the thereof, suchas diethyl phthalate. For purpose of -clarity,"in the -heretoattached-claims, the

acids. 1 Y I xttentienhes been previously. directed t the fact'thattheexpression alkanoli' includes the type of hydroxy'alipliatic radicalsin which the" niflcant, because said reagents undoubtedly havesolubility within the concentration employed.

"This Same fact 13 true in'regard to the material or materials employedas the demulsii'ying agent of our process.

We desire to point out that the superiority of the reagent ordemulsifying agent contemplated oxide, propylene'oxide,butylene oxideand glyoide,

Patent is;

in our process isbased ,upon its ability to treat certain emulsions moreadvantageously and at a somewhat lower cost than is possible with otheravailable demulsifiers, or conventional mixtures thereof. It is believedthat the particular demulsifying agent or treating agent hereindescribed will find comparatively limited application, so far as themajority of oil field emulsions are concerned, but we have found thatsuch a demulsiiy- .ing agent has commercial value, as it willeconomically break or resolve oil field emulsions in a, number of.-casewhich cannot be treated as easily 'or. at soilow a cost'with the agentsheretofore available.

In practising our processior resolving petroleum emulsionsof thewater-in-oil type, a-treating agent or demulsifyirig agent of the; kindabove described is brought into contact with orcaused to act upon theemulsion to.be treated, in any of demulsifying paratus now generallyused to resolve .or break petroleum emulsions with a chemical reagent,the

above procedure beingused either alone, or in combination with-otherdemulsifying procedure, such as'the electrical dehydration process. I YThe demulsifier herein contemplated-may be employed in connectionwithwhat iscommonly known as down-the-hole procedure.'i. e., bringing thedemulsifle'r in contact with the fluids of the well at the bottom of thewell, .or at some point prior to theemergence of said well fluids. Thisparticular type of application is decidedly feasible when thedemulsifieris used in connection'with acidification of calcareous oil-bearingstrata, especially if suspended in or dissolved in the acid employed foracidification.

The words "acidyP and "acyP and the-words acidylation and "acylation areusually used synonymously, Compounds of the type herein contemplated,and particularly for use as demulsiilers, are characterized by havingtwo diflerent types of carboxylic acid radicals, or carboxylic la ylradicals present. One type is derived from highmolal'detergeht-formingmonocarboxyacids, such as higher'fatty acids, andthe. other. type;is

. derivedfrom polybasic acids, particularly phthal-=- 7 like, or othersuitable derivatives of the words facyl, acylatedf' and facy1a'-' tion,is limited to-high .molal "monocarboxy detergent-forming acids,-whereas,- the expressions" acidyl, ffacidylated and acidylationi aremolal oxyalkylated agents, such as ethylene has a distinctly functionalsignificance.

Having thus described our invention, what we claim as-new and desire tosecure by Letters 32 carbon atoms; said acidyl radical being a polybasiccarboxy acid radical. 2. A'process for breaking petroleum emulsions orthe water-in-oil type, whichconsists in subjecting the emulsion to theaction of a demulsifier, comprising a sub-resinous acidylated derivativeof an acylated substituted urea containing at least one nitrogen-linkedalkanol radical havthe various'ways, orby any of the various aping atleast 4 and not more than 18 ether linked oxygen atoms; theacyl radicalbeing that of a detergent-forming monocarboxy acid having at least 8 andnot more than 32 carbon atoms; said acidyl radical being a polybasiccarboxy acid rad- 3. A process for breaking petroleum emulsions of thewater-in-oil type, which consists in sub-i jecting the emulsion to theaction of a demulsi- .fier, comprising a' sub-resinous acidylatedder-lvative of an acylated substituted urea containing at least onenitrogen-linked alkan'ol radical havmg atleast 4 and not more than18.ether linked oxygen atoms; the acyl radical being that of adetergent-forming monocarboxy acid having at least 8 and not more than32 carbon atomsisaid' acidyl radical being a' dibasic carboxy acid radi-Call;

4. A process for breaking petroleum emulsions of the water-in-oil type,Which'consists in subjecting the emulsion to the action of ademulsifler,comprising a sub-resinous acidylated deriv- -ative of an'acylatedsubstituted ureacontaining .at least one nitrogen-linked alkanol radicalhav ing at least 4 and notmqre than 18 other linked oxygen atoms; theacyl radical. being that oi a higher fatty acid having at least 8 andnot more radical being a than 32 carbon atoms said acidyldibasic'carboxy acid radical.

-' SLQA process for breaking petroleum emulsio of the water-in-oil type,which consists in sub- .lecting the emulsion to the actiofiof a demulsifler, comprising asub-resinous acidylated deriv ative of an acylatedsubstituted urea containing at least'one nitrogen-linked ,alkanolradical having atleast time not more than 18 ether linked connectionwith polybasic 'carboxy carbon atom chain is interrupted at least once-by an oxygen 'ai;0m, i; e., contains an ether linkage.

We have found the {type in which-the ether linkage recurs a fairly largenumber of most-desirable type of compoundi'or. other pur- I posesenumerated; Unquestionably, the recurring other linkage, particularlythat'derived from low ox en .atoms; the any! radicalv being that'or ahigher fatty acid having 18 carbon atoms; said acidyl radical'being adibasic carboxy acid rad-j ical. e

. 6. A process tor. breaking petroleum emulsions 'of the water-in-oiltyp which consists in subiecting the emulsionto'the action 01' ademulsiiler, comprising a sub-resinous acidylated deriva- .tive otanacylated'substitut'ed urea containing at -l east.one nitrogen-linkedalka'nol radical having at least 4 and not more than 18 ether linkedoxy- I times, for instanceni to .18 times-,1 represents the most.desirable type of demulsifiei' vand also the gen atoms; the acyl radicalbeing that oia'highe'r unsaturated'fatty acid h ving 18 carbon atoms;

said acidyl; radical being a dibasic'carbom acid BERNHARD

